Integrated system for converting nuclear energy into electrical, mechanical, and thermal energy and methods for using the same

ABSTRACT

Provided is an apparatus for generating electricity, mechanical energy, and/or process and district heat using a gas propellant chamber fueled with fissile material and enclosed in a sealed containment vessel which also contains an operating gas. The system allows for the operating gas to be compressed as it enters the nuclear fuel chamber where it is heated. As the operating gas exits the nuclear fuel chamber, the kinetic energy of the gas is converted to rotational energy by a variety of methods. The rotational energy is further converted to electricity, mechanical energy, and/or process and district heat. The operating gas circulates in the containment vessel and is cooled prior to re-entering the gas propellant chamber. The apparatus thereby provides a simpler and safer design that is both scalable and adaptable. The apparatus is easily and safely transportable and can be designed to be highly nuclear-proliferation-resistant.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of U.S. patent application Ser. No.16/566,977, filed Sep. 11, 2019 (now U.S. Publication No. 2020/0005955),which is a continuation of U.S. application Ser. No. 15/809,652, filedNov. 10, 2017 (now U.S. Publication No. 2019/0148027), each of which arehereby incorporated herein in their entirety by reference.

BACKGROUND

For over fifty years, electricity from nuclear energy has been generatedby large-scale power plants utilizing nuclear reactors as the energysource to heat coolant in the reactor that, directly or indirectly,drives a turbine that generates electricity. Such power generationsystems typically use the conversion of nuclear energy to thermal energyto generate electricity. Fuel assemblies containing fissile material areplaced within the reactor core and coolant flows through the reactorcore, where the heat generated by the individual fuel assemblies istransferred to the coolant. In one common commercial power generationsystem—known as a pressurized water reactor system—the nuclear-heatedprimary coolant is directed through at least one heat transfer apparatus(e.g., a heat exchanger, steam generator and piping) in which thethermal energy of the heated coolant is transferred to a secondarycoolant which is then used to drive the turbine while the reactorcoolant, now cooled, is pumped back to the reactor core in a closed loopcoolant system.

Applicant has identified a number of deficiencies and problemsassociated with conventional nuclear power generating systems. Throughapplied effort, ingenuity, and innovation, many of these identifiedproblems have been solved by developing solutions that are included inembodiments of the present invention, many examples of which aredescribed in detail herein.

BRIEF SUMMARY

In general, embodiments of the present invention provided herein includemethods and systems for nuclear power generation, particularly nuclearpower generation using a gas propellant for the energy conversion.

Embodiments of this invention could be deployed in various physicalcircumstances (on-grid; off-grid, including in remote locations; and inspace). Embodiments of this invention could also be used for a varietyof applications, including baseload electricity production, electricityto meet peaking power demand, off-grid electricity to secureinstallations, desalination; heat process production for industrial,refining and mining; and mechanical energy for various current andfuture devices, vehicles, and ships (including to power propellers).

Embodiments provided herein may relate to an apparatus for generatingelectricity comprising a gas propellant chamber comprised of an annularbody defining first and second ends, the first end of the annular bodydefining an inlet assembly that is configured to draw operating gas intothe gas propellant chamber and the second end defining an exhaustassembly that is configured to expel operating gas from the gaspropellant chamber; a nuclear fuel chamber positioned within the annularbody of the gas propellant chamber between the first and second ends,the nuclear fuel chamber configured to heat the operating gas; acompressor positioned proximate the first end of the gas propellantchamber, the compressor configured to compress the operating gas priorto entry into the nuclear fuel chamber; a conversion apparatuspositioned proximate the second end of the gas propellant chamber, theconversion apparatus configured to convert kinetic energy of theoperating gas exiting the nuclear fuel chamber into rotational energy;and a drive shaft extending axially through the gas propellant chamberbetween the first and second ends, the drive shaft coupling thecompressor to the conversion apparatus.

In some embodiments, the compressor may be an axial compressor. In someembodiments, the compressor may be a centrifugal compressor. In someembodiments, the compressor may be a centrifugal compressor without adiffuser. In some embodiments, the gas propellant chamber may be housedin a containment vessel, the containment vessel having an inner wall anddefining a region between the inner wall and the annular body of the gaspropellant chamber, the region forming a bypass for operating gas topass around the annular body. In some embodiments, the apparatus mayfurther include a circulation fan rotationally coupled to the compressorand conversion apparatus and disposed proximate to the compressor,wherein the circulation fan is configured to draw operating gas into thecompressor and the bypass around the nuclear fuel chamber.

In some embodiments, the operating gas comprises air, argon, helium,carbon dioxide, or combinations thereof. In some embodiments, thenuclear fuel chamber may house nuclear fuel elements and defines one ormore interior chambers forming one or more elongate flow paths withinthe nuclear fuel chamber for the operating gas to pass through and beheated by the nuclear fuel elements. In some embodiments, the nuclearfuel chamber may house nuclear fuel elements and defines one or moreinterior chambers forming one or more elongate flow paths within thenuclear fuel chamber for the operating gas to pass through and be heatedby the nuclear fuel elements, the one or more elongate flow pathsdisposed in a spiral configuration.

In some embodiments, the exhaust assembly may comprise a nozzleconfigured to propel the operating gas at the conversion assembly andthe conversion apparatus comprises a turbine assembly, wherein theturbine assembly comprises turbine blades and is configured such thateach of the turbine blades rotate during operation of the turbineassembly.

In some embodiments, the compressor may comprise compressor blades andis configured such that each of the compressor blades rotate duringoperation of the compressor.

In some embodiments, the exhaust assembly may comprise a nozzle and theconversion apparatus may comprise a turbine assembly with at least oneblade assembly in line with an exit of the nozzle.

In some embodiments, the apparatus may comprise a flywheel positioneddownstream of the nuclear fuel chamber and rotationally coupled to thecompressor and conversion apparatus.

In some embodiments, the nuclear fuel chamber may rotate along a commonaxis with the compressor and conversion assembly.

In some embodiments, the gas propellant chamber may be disposed in acontainment vessel, the containment vessel having an inner wall defininga circulation path for the operating gas to travel from the conversionapparatus to the inlet assembly. In some embodiments, the gas propellantchamber may be disposed in a containment vessel, the containment vesselhaving an inner wall defining a circulation path for the operating gasto travel from the conversion apparatus to the inlet assembly, whereinthe circulation path has a first diameter and a second diameter, thesecond diameter being larger than the first diameter and disposeddownstream of the first diameter. In some embodiments, the containmentvessel may comprise a first surface and a second surface, the firstsurface disposed between the circulation path and the second surface,and a cooling mechanism between the first and second surface such thatthe operating gas flowing through the circulation path is cooled uponcontact with the first surface. In some embodiments, the circulationpath may comprise cooling pipes disposed along the circulation path incontact with the operating gas. In some embodiments, the conversionapparatus may comprise a nozzle connected to a rotor wherein the rotoris in communication with a stator belt and, wherein the nozzle and rotorare configured to rotate along an axis as the operating gas enters andexits the nozzle thereby generating electricity. In some embodiments,the apparatus may include a propeller rotationally coupled to thecompressor and conversion apparatus.

The above summary is provided merely for purposes of summarizing someexample embodiments to provide a basic understanding of some aspects ofthe disclosure. Accordingly, it will be appreciated that theabove-described embodiments are merely examples and should not beconstrued to narrow the scope or spirit of the disclosure in any way. Itwill be appreciated that the scope of the disclosure encompasses manypotential embodiments in addition to those here summarized, some ofwhich will be further described below.

BRIEF DESCRIPTION OF THE FIGURES

Reference will now be made to the accompanying drawings, which are notnecessarily drawn to scale, and wherein:

FIG. 1 illustrates a partial section view of a nuclear power generationapparatus having a rotationally coupled compressor and conversionapparatus coupled through a nuclear fuel chamber in accordance with someembodiments discussed herein;

FIG. 2 illustrates a partial section view of a nuclear power generationapparatus having an integrated conversion apparatus and exhaust assemblyin accordance with some embodiments discussed herein;

FIG. 3 illustrates a section view of a nuclear power generationapparatus having a nuclear fuel chamber including helical flow paths inaccordance with some embodiments discussed herein;

FIG. 4 illustrates a partial section view of a nuclear power generationapparatus having a circulation fan rotationally coupled to a compressorand an integrated conversion apparatus in accordance with someembodiments discussed herein;

FIG. 5 illustrates a partial section view of a nuclear power generationapparatus having a stator/rotor combination integrated into the exhaustassembly in accordance with some embodiments discussed herein;

FIG. 6 illustrates a detail view of an exhaust assembly in accordancewith some embodiments discussed herein;

FIG. 7 illustrates a detail view of an axial compressor inlet assemblyin accordance with some embodiments discussed herein;

FIG. 8 illustrates a detail view of a centrifugal compressor inletassembly in accordance with some embodiments discussed herein;

FIG. 9 illustrates a detail view of a circulation fan and compressorinlet assembly in accordance with some embodiments discussed herein;

FIG. 10A illustrates a detail view of a nuclear fuel chamber inaccordance with some embodiments discussed herein;

FIG. 10B illustrates a detail view of a nuclear fuel chamber inaccordance with some embodiments discussed herein;

FIG. 11 illustrates a cross-section of the nuclear fuel chamber alongline 11-11 shown in FIG. 3 in accordance with some embodiments discussedherein;

FIG. 12 illustrates a detail view of an exhaust assembly in accordancewith some embodiments discussed herein;

FIG. 13 illustrates a detail view of an exhaust assembly in accordancewith some embodiments discussed herein;

FIG. 14 illustrates a cross-section of the exhaust assembly nozzle alongline 14-14 shown in FIG. 1 in accordance with some embodiments discussedherein;

FIG. 15 illustrates a cross-section of the exhaust assembly nozzle alongline 15-15 shown in FIG. 5 in accordance with some embodiments discussedherein; and

FIG. 16 illustrates a partial section view of a nuclear power generationapparatus in accordance with some embodiments discussed herein.

DETAILED DESCRIPTION

Some embodiments of the present invention will now be described morefully hereinafter with reference to the accompanying drawings, in whichsome, but not all embodiments of the inventions are shown. Indeed, theinvention may be embodied in many different forms and should not beconstrued as limited to the embodiments set forth herein; rather, theseembodiments are provided so that this disclosure will satisfy applicablelegal requirements. Like numbers refer to like elements throughout.

While no serious threats to public health or the environment haveoccurred in the United States from the operation of nuclear reactors inelectrical power generation systems, the public perception of nuclearreactors includes several safety concerns, although many of theseconcerns may be exaggerated. Due to the size of the current commercialnuclear power generation stations as well as the design and inherentoperational characteristics of the nuclear reactor, nuclear powergeneration stations must, to the extent possible, be operatedcontinuously. Further, locations suitable for such large powergeneration facilities are limited, especially considering that largeelectricity demands are typically found in densely populated areas whilesparsely populated areas usually have small electricity demands relativeto the electricity supplied by a conventional commercial nuclear powergenerating station. Finally, many of the existing nuclear reactors arereaching the end of their originally licensed operational periods, whileother reactors are being closed or are being considered for closing foreconomic reasons, primarily in unregulated markets.

The potential reduction in our existing nuclear fleet is occurring at atime of growing public interest in clean energy due in part to climatechange concerns. Over the past decade, increasing industry and publicinterest has been given to small modular reactors (“SMRs”) due to thisreduction in our existing nuclear fleet and the recognized advantages ofSMRs over current large nuclear reactors. These advantages includeenhanced safety due to passive safety; lower capital costs due tomodular components and factory manufacture; siting flexibility; greaterapplications such as heat process; and more proliferation resistance.The concerns about climate change have also led during the past decadeto increased interest in SMRs. SMRs include both water-cooled reactorsand other types of reactors, such as gas-cooled high-temperaturereactors, molten-salt reactors and lead-cooled fast reactors, with someof these reactors also being classified as “advanced” SMRs.

Provided is an improved system for producing energy and generatingelectricity using a nuclear fueled reactor and methods of using thesame. The apparatus may eliminate certain heat exchangers, piping, andother thermal conversion machinery typically utilized in other nuclearpower generation apparatus. In contrast to these conventional systems,the present apparatus utilizes kinetic energy from the operating gasexiting the nuclear-fueled reactor to directly generate rotationalenergy which can then be converted to electricity or mechanical energy.

The present apparatus uses a single phase coolant, in particular, a gasphase coolant. In contrast to prior systems, the present apparatus usesgas (single phase fluid) as both the reactor coolant (heat removal agentand carrier) and working fluid in the energy conversion. In addition,atmospheric gasses (ambient gasses) may be used. Further, the nuclearenergy source and conversion of kinetic energy to rotational energy andthen to electricity can be integrated in a manner that eliminates thecomplex array of heat exchangers and piping often used in conventionalsystems. The present apparatus thereby provides an integral unitconfiguration that is a simpler, more reliable and safer design, onewhich may reduce the risks of heat exchanger breakdowns, leaks ofvarious kinds and may reduce the risk of core damage.

The present apparatus has a scalable and adaptable design, being trulymodular and capable of manufacture in a factory, where the nuclear fuelcan be securely loaded within an integral unit. Factory manufacturemeans that the apparatus would have lower and more predictable capitalcosts. The apparatus is easily and safely transportable, and theapparatus can be designed to be highly nuclear-proliferation-resistant.The apparatus is capable of wide-spread deployment over variousapplications, such as electricity generation, process heat,desalination, and power production in space.

In the present apparatus, the kinetic energy to generate electricity isproduced by heating a pressurized operating gas flowing through anuclear fuel core in a gas propellant chamber. The gas has dualfunctions—it is a primary coolant for the nuclear fuel core as well asworking fluid for the energy conversion. Once heated, the operating gasdirectly impacts a conversion assembly for converting kinetic energy torotational energy. The conversion assembly may include a variety ofcomponents in a variety of configurations and generally includes a bladeassembly where the blades are directly impacted by the operating gas.

The conversion assembly is in communication with a generator. As theoperating gas impacts the conversion assembly, a significant portion ofthe kinetic energy of the gas is converted to rotational energy bycausing the blades of the conversion assembly to rotate. The rotationalenergy is then converted to electricity by way of one or more generatorsin communication with the conversion assembly. The conversion assemblymay also include a drive shaft that could convert the rotational energyto mechanical energy for other energy production (such as to power apropeller), separately or in addition to electricity generation. As theoperating gas exits the conversion assembly, the operating gas isdispersed in the containment vessel, where it can travel back to theinlet assembly of the gas propellant chamber for recycle. The spinningblades of the conversion assembly may help disperse the operating gasthrough the containment vessel. Accordingly, the present apparatus canbe designed as a closed system, where the components are enclosed in asealed containment vessel and the operating gas is continuously recycledthrough the apparatus.

The apparatus is generally designed to focus on the fluid transportationthrough the apparatus, through each of the inlet assembly, nuclear fuelchamber, and exhaust assembly, to increase the velocity and volume offluid impacting the conversion assembly. Various components of theapparatus and their arrangement in the apparatus allow for the highvelocity and volume of fluid through the apparatus as will be discussedthroughout the present disclosure. The apparatus allows for the fluid tobe propelled at the conversion assembly for high efficient energyconversion. For instance, the conversion assembly may include a turbineassembly in communication with a compressor. Both the turbine assemblyand compressor include blades that rotate during operation such that nostationary blades are present during operation. The removal ofstationary blades may avoid any energy losses or decrease in velocitydue to the operating gas coming in contact with the stationary blades.In general, neither the turbine assembly nor the compressor include adiffuser, which in conjunction with the turbine or compressor, mayreduce the velocity of the fluid through the apparatus.

The turbine assembly and compressor are connected by a drive shaftthrough the nuclear fuel chamber such that both components rotate andcontinuously drive each other in the apparatus and avoid energy lossesthat may occur with two separately driven components (e.g., where thecompressor and turbine assembly are driven separately). In addition,high performance bearings (e.g., magnetic bearings) may be used in thecomponents (e.g., the turbine assembly) to minimize friction and therebyreduce reductions in velocity through the apparatus.

In some embodiments, the containment vessel housing each of the inletassembly, nuclear fuel chamber, and exhaust assembly may be designedsuch that the operating gas is able to expand and thus cool in thecontainment vessel prior to re-entering the inlet assembly. Thecontainment vessel may also include other cooling mechanisms which wouldbe incorporated in a manner to facilitate, or at least not substantiallyimpede, the gas transportation through the apparatus.

In some embodiments, the configuration of the nuclear fuel chamber maybe such to promote the velocity of the operating gas exiting the inletassembly (e.g., compressor) through the nuclear fuel chamber. This mayoccur by, for example, helical or spiral flow paths through the nuclearfuel chamber or otherwise configuring the flow paths to funnel throughthe nuclear fuel chamber, and various other configurations. The helicalflow paths, for example, may minimize changing the operating gas's flowvector. The helical flow paths may include entrances that are beveled orotherwise aerodynamically shaped to minimize disruption or drag on theentering gas flow. The gas propellant chamber and its components and thecontainment vessel (including the circulation path) are generallydesigned to minimize air and surface friction.

The present apparatus provides an innovative carbon-free energy sourcefor electricity, mechanical energy production, and process heat thatimproves safety and is highly proliferation-resistant, capable offactory manufacture, and has an adaptable design to maximize potentialapplications. The present apparatus may be used for general electricityproduction (including clustering units together) or for specialpurposes, such as localized use or meeting peak demands, providingenergy source for remote regions or regions with limited infrastructure,or applications where localized power source is needed and no fuelsource is readily available. The apparatus may also be used to provide,concurrently with or separately from the electricity, process heat andmechanical energy for various applications.

As used herein, the term “gas propellant chamber” generally refers tothe structure housing part or all of the inlet assembly, the nuclearfuel chamber, and the exhaust assembly. The components of the gaspropellant chamber may be physically connected and/or separated into twoor more parts. Regardless, the gas propellant chamber is designed forcontinuous flow of the operating gas through the apparatus to allow theoperating gas to be propelled at the conversion assembly and thus, ingeneral, does not include significant physical or operational barriersbeyond the main components themselves (e.g., compressor, turbineassembly, nuclear fuel chamber). That is, while the pressure andtemperature of the operating gas increases along the gas propellantchamber, the operating gas generally does not experience pressure ortemperature barriers between components defining distinct, sharppressure differences between components. The pressure and temperature atthe outlet of the compressor in the present apparatus satisfy thepressure and temperature requirements for the inlet of the nuclear fuelchamber and the nuclear fuel chamber is then designed so that thepressure and temperature at the outlet of the nuclear fuel chambersatisfy the velocity required at the inlet of the conversion assemblyfor a specific configuration. This more seamless approach results is animprovement in gas transportation through the apparatus (e.g., reductionin velocity losses across components, including pressure barriers). Themore integrated system and seamless transition between components allowsfor a more compact and efficient system with fewer energy losses. Forinstance, additional connections between components (e.g., physicalbarriers, piping changes, stationary blades, etc.) may impose an energyloss (e.g., about 10-20% loss per component).

The gas propellant chamber is designed for operating gas to enterthrough the inlet assembly, be heated in the nuclear fuel chamber, andexit through the exhaust assembly at a higher velocity than when theoperating gas entered the chamber. Accordingly, the operating gas ispropelled out of the chamber to then directly impact a component forconverting the kinetic energy to rotational energy (a “conversionassembly”), such as a turbine or propeller assembly. The components ofthe gas propellant chamber can be designed to accelerate the operatinggas when exiting the nuclear power generation apparatus to the desiredvelocity. Due to the integration of the components in the gas propellantchamber, the system may experience a single temperature differentialacross the chamber (e.g., as opposed to different temperaturerequirements for the outlet of one component and the inlet of thesucceeding component). In some embodiments, the temperature differenceacross the gas propellant chamber may be about 300 K to about 1000 K,such as about 350 K to about 900 K, about 400 K to about 800 K, about400 K to about 600 K, or about 400 K to about 500 K. The temperaturedifference may be related to the length of the flow path through the gaspropellant chamber. For instance, the flow path may be about 5 m toabout 15 m, about 7 m to about 12 m, or about 8 m to about 10 m inlength. The single temperature differential may reduce energy losses andincrease efficiency.

The “nuclear fuel core,” which may be generally referred to as the “fuelcore,” is housed in the “nuclear fuel chamber,” which is part of the gaspropellant chamber structure. The nuclear fuel core contains nuclearfuel elements including fissile material, such as uranium, plutonium,thorium, or a mixture thereof in the specific desired proportion.

The nuclear fuel chamber includes flow paths running longitudinallythrough the nuclear fuel chamber for the operating gas to flow throughand transfer heat from the nuclear fuel elements to the operating gas.The flow paths are configured such that they run from one end of thenuclear fuel chamber to the other end of the nuclear fuel chamber. Otherchannels or openings with a variety of configurations or dimensions, inlieu of or in addition to the longitudinal paths, may also run throughthe nuclear fuel chamber for the operating gas to flow, and passages mayalso be included for the operating gas to flow around the fuel core.

In some embodiments, the nuclear fuel chamber may include helical orgeometrical flow paths for the operating gas to travel through thenuclear fuel chamber. Such helical flow paths may be in lieu of, or insome cases, in addition to, longitudinal flow paths. Such helical flowpaths may provide increased effective travel length through the chamber(and thus, increased heating per length of nuclear fuel core) whilemaintaining a compact chamber. Further, the helical flow paths may helpmaintain the velocity of the operating gas by maintaining the helicalflow exiting the compressor. For instance, as the compressor isgenerally designed without stationary blades, the compressor results ina helical operating gas flow that can then be maintained in the nuclearfuel chamber. The helical or geometrical flow paths would be routedthrough the nuclear fuel core in a manner to achieve the most effectivecooling of the fuel core. This may include a proportionally greaternumber of flow paths originating at the perimeter of the fuel core andthen passing toward the center of the fuel core and having flow paths ofvarying diameters to increase the flow path in the hottest areas of thefuel core.

The nuclear fuel chamber may further incorporate a control system tocontrol the nuclear reaction. For instance, the nuclear fuel elementscan be manipulated to begin the nuclear fissioning process within thenuclear fuel chamber leading to a sustained nuclear reaction. Thecontrol elements may be manipulated to regulate the chain reactionwithin the nuclear fuel chamber, thereby regulating the energy producedby the apparatus. The nuclear fuel chamber can be designed to provide asustained reaction that can continue for a period of years, subject toplanned and unplanned stoppages. In some embodiments, the nuclear fuelchamber may be a fast spectrum reactor, which may offer a longer fuellife, a higher burn-up of nuclear fuel, and a more compact assembly.Further, in some embodiments, especially for space applications sincegravitational forces are minimal, the nuclear fuel chamber may bedesigned to rotate with the blades of the conversion assembly, such asthe rotating blades of a turbine or propeller assembly, and compressorof the inlet assembly. Such rotation may facilitate gas transportationand the rotating chamber would have a flywheel effect. Further, in someembodiments, two or more nuclear fuel cores (or fuel assemblies) may beclustered in one nuclear fuel chamber with a single drive shaft runningthrough the center of the nuclear fuel chamber and connected to thecompressor and the energy conversion assembly. In some embodiments, twoor more gas propellant chambers may be contained on parallel axes in thecontainment vessel. In such clustered configurations, the nuclear fuelcores (or fuel assemblies) may be subcritical for transportationpurposes and then become critical once at the desired site byneutronically connecting the clustered cores or chambers through aconnecting medium. Various configurations of the nuclear fuel chamberand nuclear fuel elements are available as further discussed herein.

Contemporaneously with beginning the fissioning process in the nuclearfuel chamber, rotational thrust may be applied, such as via a motor orflywheel, to a rotational shaft (“drive shaft”) to commence the rotationof certain components of the apparatus, such as one or more compressors,the blades of the turbine assembly, and one or more circulation fans.

The exhaust assembly of the gas propellant chamber can include a varietyof components and may generally be designed to further increase thevelocity of the operating gas exiting the nuclear fuel chamber. Theexhaust assembly may also include a conversion assembly for directlycapturing a significant portion of the kinetic energy and converting theenergy into rotational energy and may further include components forconverting the rotational energy into electricity. As will be discussedfurther below and shown in the accompanying figures, the exhaustassembly may include various components in a variety of configurations,such as a nozzle designed to further increase the velocity of theoperating gas and/or one or more turbines in line with the nozzle,rotor/stator assemblies for directly converting the rotational energyinto electricity within the exhaust assembly, etc.

The turbine assembly may include turbine blades disposed in an arrayaround the drive shaft. As noted above, the turbine blades are generallydesigned to rotate during operation, rather than being an array ofrotating and stationary blades as seen in some jet engines. An intricatearray, including stationary blades, such as that seen in jet engines maynot be workable because it may impede the flow of the working fluidexiting the turbine assembly such that the velocity of the working fluidis too slow to provide continued adequate circulation (gastransportation) through the containment vessel. More than one array ofturbine blades may be used, such as seen in FIG. 4 and discussed in moredetail below. FIG. 4 allows for continuous gas transportation while alsointegrating a stator belt within the containment vessel for generatingelectricity. The overall number and configuration of the turbine arraysmay be limited by the dimensions of the system (e.g., total gas pathwaylength). The turbine assembly is generally designed to increase thespeed of the turbine blades as the operating gas is propelled at theblades, leading to increased generation of energy. The turbine bladesmay be designed per the application and power rating of the apparatus,all of which may be used to design the nuclear fuel chamber. In someembodiments, magnetic bearings or other high-performance bearings (suchas oil bearing with gas seals) may be utilized to minimize the friction.In some embodiments, the turbine blades may be angled and curved tooptimize the turbine assembly's angular velocity based on the speed andangle at which the operating gas may be impacting the turbine blades,subject to other aerodynamic considerations. The shape and length of theturbine blades may also need to take into consideration the need toincrease gas transportation, including gas transportation after exitingthe turbine assembly (e.g., minimizing an unnecessary impediment of thegas flow, plus directing the operating gas through the circulationpath). The turbine blades may differ radially to capture more energyefficiently.

In general, the focus of the design of the turbine assembly may be onincreasing the rotation of the turbine blades. In contrast, traditionaljet engines are based on taking a high rate of incoming air,accelerating the air along with the mass of the combustion products,which then provides thrust to the engine to propel the plane, with thetrust being proportional to the mass of the material and the increase inmass velocity. In this regard, jet engines are designed to work inspecific dynamic conditions (thus, requiring the production of thrust).A portion of the jet engine's heat energy is thus converted to usefulwork in propelling the plane forward but another typically significantportion is lost and dissipated into the atmosphere. However, in thepresent apparatus, the apparatus is generally stationary when inoperation. That is, during operation, the components of the apparatusare moving, however, the apparatus, as a whole, is not moving,highlighting the requirement that the turbine in the apparatus besuitable in achieving the overall gas transportation requirements of theapparatus. Such distinction fundamentally changes how operating gas istransported through the apparatus. There are various other ways in whichthe operating requirements and parameters of jet engines would differ,such as the need for fuel economy and noise reduction in jet engines.

One or more components of the gas propellant chamber are generallynuclear qualified and suitable for high temperature operations as theapparatus provides high power density in a compact system. For instance,ceramic materials may be used for the components. The components mayalso be configured for sustaining high pressures, such as up to about 10MPa, such as up to about 8 MPa. The nuclear qualified components may becertified to withstand radiation environments and be reliable andsufficiently sealed to prevent radioactivity releases. Materials may beselected to make sure there are no corrosion effects or other types ofdegradation.

In embodiments for generating electricity, for example, the apparatuswill generally include a generator or similar component for convertingrotational energy to electricity. The generator may be any suitablegenerator and may be incorporated into the apparatus in a variety ofconfigurations. For instance, in some embodiments, electricity may becreated using a generator downstream of the turbine or propellerassembly, while in some embodiments, a rotor/stator combination may beincorporated in the exhaust assembly. In some embodiments, the generatormay be disposed outside of the containment vessel, while in someembodiments, the generator may be disposed within the containmentvessel. Further, in some embodiments, the generator may be anelectrostatic generator.

In some embodiments, the apparatus may include a containment vessel forhousing one or more of the components of the apparatus. The containmentvessel houses the gas propellant chamber and may provide a path forrecirculation of the operating gas (“circulation path”). The containmentvessel may be constructed of any suitable material and in any suitableconfiguration without deviating from the intent of the presentdisclosure. For instance, radioactive shielding may be included asneeded throughout the containment vessel, such as in and around thenuclear fuel chamber. Further, in some embodiments, the containmentvessel may have more than one layer, such as an inner containment vessellayer and an outer containment vessel layer. In some embodiments, it maybe beneficial to have an outer containment vessel layer defining avacuum around the inner containment vessel layer. For instance, an outercontainment vessel may be included that operates at negative pressurewhile the inner containment vessel may have pressurized gas and, in someembodiments, may include piping to vent the gas.

The containment vessel may be a sealed structure and may contain theoperating gas and the nuclear fuel chamber as well as other componentsof the apparatus. The containment vessel can be designed to comply withregulatory, safety, and security requirements, and may have any shapethat complies with the above mentioned requirements, fulfills itspurpose with regard to the configuration of the equipment therein, andsatisfies other design parameters, such as operating gas transportationwithin the apparatus and incorporating the mechanics needed to cool thecirculating operating gas such that when the operating gas enters thenuclear fuel chamber, the temperature of the operating gas has beenlowered to the appropriate level.

For instance, the interior of the containment vessel may be shaped tofacilitate the transportation and cooling of the gas within thestructure. In some embodiments, the containment vessel may be designedto provide a circulation path of about two or three times the diameterof the path of the operating gas through the exhaust assembly and insome embodiments, the containment vessel may extend at least about 1 or2 meters on either side of the exhaust assembly and the inlet assembly.That is, the circulation path may be significantly larger than the pathof the operating gas through the gas propellant chamber, particularlythrough, the exhaust assembly. Accordingly, the operating gas may becooled significantly when traveling through the circulation path back tothe inlet assembly.

The containment vessel may also incorporate mechanisms for cooling theinterior sides of the structure, may include cooling pipes in theinterior of the containment vessel as further means for cooling thecirculating gas thereby transferring some of the heat to secondarymedia, and may include additional passages for the operating gas totravel and cool down (e.g., through additional heat exchangers). Thelarger the temperature difference between the inlet assembly and theexhaust assembly, the more efficient the system will be. The operatinggas may be cooled in the containment vessel through not just radiantcooling, which may be insufficient due to the large temperaturedifferential required between the exhaust assembly and inlet assembly,but also through forced convection and conduction. In some embodiments,a cooling mechanism may be disposed between the inner and outercontainment vessel layer such that operating gas traveling through thecontainment vessel may be cooled upon contact with the inner containmentvessel layer (the outer containment vessel layer generally not being incontact with the operating gas). Circulation fans for facilitating thetransportation of the operating gas through the structure may also beincluded in the containment vessel. The drive shaft for some of thesefans may be coupled to the drive shaft for the compressor and turbineassembly to reduce energy losses. The apparatus can also be scaleddepending on the uses required for the system and can be designed ineither a large or a very small integral reactor-converter configuration.

The operating gas may be any suitable gas, such as air, argon, helium,carbon dioxide, or other suitable gas. For instance, the operating gasmay include atmospheric gas in the environment on Earth, Mars, or otherplanets.

An inlet assembly is generally configured to draw operating gas into thenuclear fuel chamber and may do so by including various components suchas one or more compressors, circulation fans, and other similarcomponents. The inlet assembly may be shaped to draw operating gas intothe nuclear fuel chamber and/or be positioned along the apparatus toincrease the draw of operating gas into the nuclear fuel chamber. Insome embodiments, a compressor may be added to the inlet assembly todirect the operating gas to the nuclear fuel chamber and furtherincrease the pressure of the operating gas, thereby increasing theefficiency of the apparatus. A compressor to compress the operating gasentering the inlet assembly may be positioned in the inlet assembly witha drive shaft. The drive shaft may run through a channel in the nuclearfuel chamber thereby connecting the compressor to a conversion assembly.Coupling the drive shaft to the compressor and conversion assemblythrough the nuclear fuel chamber allows the power from the conversionassembly (e.g., turbine assembly) to directly rotate the compressor,thereby minimizing the energy losses resulting from using a differentpower source. Unlike prior systems, the drive shaft couples thecompressor and conversion assembly through the nuclear fuel chamber.Coupling of the components through the nuclear fuel chamber provides afully integrated system and improves gas transportation through theapparatus and allows for smaller overall dimensions. A variety ofconfigurations of a compressor may be used, as will be discussedfurther, such as an axial compressor or centrifugal compressor. Thecompressor may have one or more stages of compressor blades, though witheach stage, the compressor blades are generally configured to rotateduring operation. That is, the compressor is generally designed to notinclude stationary blades, which may impede the flow of the operatinggas through the apparatus, reducing the velocity of the gas and alsoresulting in energy losses. In this regard, a diffuser may also not beused with the compressor as a diffuser may impede the flow through thecompressor and reduce the velocity of the operating gas through theapparatus. The compressor in the present apparatus may be integratedwith the other components in the gas propellant chamber to provide aseamless operating transition between components.

In some embodiments, the apparatus may include heat extraction passagesto process heat for commercial or other purposes. In addition to suchheat extraction passages, it may be beneficial to include heatexchangers for process or district heat in cases where the operating gasis not inert or the containment vessel is a closed vessel. The heatexchanger may also aid in cooling the gas as it circulates.

In some embodiments, the apparatus may include one or more circulationfans to facilitate gas transportation through the structure. Thecirculation fans may be connected or coupled to a drive shaft of theapparatus connecting various components of the apparatus. By couplingthe circulation fan to the conversion assembly and the compressorthrough the nuclear fuel chamber, the addition of the circulation fanprovides improved gas transportation while not requiring a separatepower supply to power the circulation fan.

Bypasses may also be included in the apparatus to bypass the nuclearfuel chamber. In this regard, a circulation fan may be included todirect operating gas to the bypass (as well as to the nuclear fuelchamber) by positioning the circulation fan upstream of both the inletto the nuclear fuel chamber and the bypasses. Bypasses may providecooling, and thus, better control, of the nuclear fuel chamber as wellas improve gas transportation (and gas velocity) through the apparatus.The bypass allows for a greater operating gas volume and may beunrestricted or only partially restricted through the gas propellantchamber to aid in gas transportation through the apparatus, includingthe circulation path.

Various other components may be included throughout the apparatus suchas cooling pipes, flywheels, wiring, sensors, controls, etc. Forinstance, in some embodiments, the apparatus may incorporate a flywheel,which may be coupled to or otherwise in communication with the energyconversion assembly, a generator or similar apparatus. The dimensionsand configuration of the flywheel can be determined by several factors,such as the flywheel's expected angular velocity. In some embodiments,the flywheel may be supported and stabilized by magnetic bearings orother high-performance bearings to minimize surface friction. Theflywheel may incorporate, to the extent feasible, the current state ofthe art for high-performance flywheels in the design and integration ofthe flywheel in the apparatus. The flywheel may provide flexibility tothe overall design and provide backup electrical generation, as well asaugment the rotational energy provided to rotate certain components ofthe apparatus such as the compressor or fan. The flywheel may also offeran added safety benefit to the apparatus since the flywheel can beengaged if needed to continue the circulation of the operating gas inthe event the fuel core needs to be shutdown. The flywheel also offersthe advantage of using or storing renewable-fuel-generated electricity,especially during peak production times for such fuel. The flywheel maybe housed in a vacuum chamber. In some embodiments, the flywheel may beincorporated into the containment vessel along with the inlet assembly,nuclear fuel chamber, and exhaust assembly.

The flywheel, as well as the generator, may offer the opportunity tobegin the initial rotation of the operating gas in the apparatus byengaging and spinning the blades of the conversion assembly or anysimilar apparatus, and potentially the spinning of one or morecompressors and/or fans disposed at the inlet assembly of the gaspropellant chamber.

In some embodiments, the apparatus can serve as a motor with a driveshaft used to provide mechanical energy. For instance, the drive shaftcan be attached to a propeller or other propulsion assembly. Forexample, the apparatus could be used in a submarine to power thepropeller for propulsion, while also generating electricity and districtheating for use on board the submarine.

The apparatus is suitable to operate regardless of external environments(including on the moon or other planets), and with or without utilizingthe ambient gas in such environments as the system's operating gas. Insome embodiments, the apparatus may be designed to operate undergroundor underwater. For instance, the apparatus may be submerged under water.Such underground or submerged configurations may provide safety andsecurity benefits. Further, the present apparatus has significantpotential for space power production, especially since in outer spacethe cooling issues would be minimal.

In some embodiments, two or more apparatuses could be sited at onelocation to share certain of the infrastructure and staffing at thelocation, as a multi-unit plant.

In some embodiments, the present apparatus may include a nuclear fuelcore integrated with one or more components traditionally found in a jetengine (e.g., a turbofan, turbojet or ramjet, as well as other typesthat may be later conceived or developed) adapted for the presentapparatus. For instance, in some embodiments, diffusers, which may befound in some jet engines, may not be needed and may, instead, createdrag by decreasing the velocity of the operating gas.

The operating gas exiting the nuclear fuel chamber can be used togenerate electricity by various components. For instance, as discussedfurther below, one or more turbines, nozzles, blade assemblies,propellers, etc. may be used to capture the kinetic energy from theoperating gas and convert such to rotational energy. Variousconfigurations may be used without deviating from the intent of thepresent disclosure. For instance, the operating gas may be directed atand rotate the blades of a propeller assembly in proximity to theexhaust assembly. A turbine or propeller assembly may be incommunication with a generator or other apparatus for converting therotation of the shaft or other component(s) of the propeller assembly toelectricity, such as a stator and rotor assembly. In some embodiments,the generator may be integrated, wholly or partially, into theconversion assembly.

As shown herein, the present apparatus addresses significant challengesof gas transportation and cooling. Other apparatuses have been concernedwith transportability of the apparatus, which means segmenting thecomponents or modules for transportation purposes and ensuring that themodules meet dimensions of a cargo unit or trailer. As a result, thechallenges of gas transportation and cooling cannot be adequatelyaddressed within these prior configurations. Transporting the presentapparatus may be improved by controlling the pressure of the system,adding absorbers, and various other methods. For instance, thecontainment vessel may be installed onsite and then the gas propellantchamber may be added thereto. In addition, the fully integrated approachof the present apparatus allows for smaller dimensions than those ofother transportable apparatuses if such other apparatuses were adaptedto adequately address gas transportation and cooling.

FIG. 1 illustrates a partial section view of a nuclear power generationapparatus in accordance with some embodiments discussed herein. Inparticular, FIG. 1 illustrates a nuclear power generation apparatus 100comprising a containment vessel 102 housing a gas propellant chamber 126which includes an inlet assembly 104, nuclear fuel chamber 106, andexhaust assembly 108. The gas propellant chamber 126 has an annularbody. The containment vessel 102 also defines a circulation path 110 forthe operating gas to flow in the closed system. As shown in FIG. 1, inthis embodiment, the inlet assembly 104 includes a compressor 712, suchas an axial compressor as illustrated in FIG. 1, disposed in the inletport or first end of the annular body of the gas propellant chamber 126.In the embodiment illustrated in FIG. 1, the inlet port of the annularbody of the gas propellant chamber 126 has a cross section thatdecreases along the length of the inlet port where the compressor 712 isdisposed. Such restriction in the cross section may help to compress theoperating gas to be directed to the nuclear fuel chamber. The nuclearfuel chamber includes nuclear fuel elements 1014, and the exhaustassembly 108 includes a nozzle 616 and a turbine assembly 618. Thenozzle 616 forms the exhaust port or the second end of the annular bodyof the gas propellant chamber 126. The nozzle may restrict the flow areaof the operating gas to increase the velocity of the gas. The flow ofthe operating gas exiting the nuclear fuel chamber drives the turbineassembly. The compressor 712 is rotationally connected to the turbineassembly 618 by the drive shaft 120 and is driven by the drive shaft'srotation. The turbine assembly 618 is also connected to a generator 122,shown schematically, and a flywheel 124.

In the embodiment illustrated in FIG. 1, the compressor 712, turbineassembly 618, generator 122, and flywheel 124 rotate along a singleaxis. However, in other embodiments, one or more of the components mayrotate along different axes. For instance, in some embodiments, it maybe desired to have the flywheel 124 rotate along an axis different thanthat of the compressor 712 and turbine assembly 618.

In the foregoing configuration, the location of the blades of theturbine assembly in relationship to the outlet of the nuclear fuelchamber may be determined by several parameters, such as the velocityand temperature of the operating gas at certain distances from theoutlet of the nuclear fuel chamber. The blades may span partially, oralternatively entirely, the inner circumference of the containmentvessel at the point where the operating gas contacts the blades,depending on the specific configuration of the blades, the specificconfiguration of the apparatus and its other components (including thecirculation path) and the specific gas transportation requirements ofthe specific apparatus configuration. Magnetic bearings or otherhigh-performance bearings may be utilized to minimize the surfacefriction at the base of the spinning blades of the turbine assembly andto maximize the angular velocity of the blades.

FIG. 14 illustrates a cross-section of the exhaust assembly nozzle alongline 14-14 shown in FIG. 1 in accordance with some embodiments discussedherein. In particular, FIG. 14 illustrates the shaft 120, turbine blades121 of the turbine assembly 618, interior of the nozzle 119,cross-section of the nozzle wall 117, bypass 130 (along line 14-14, thebypass opens to the turbine blades 121 of the turbine assembly 618),cross section of the containment vessel 134, and containment vessel 102along the cross-section line 14-14 of FIG. 1.

In the embodiment illustrated in FIG. 1, a bypass 130 is disposedbetween the gas propellant chamber 126 and the inner wall 128 of thecontainment vessel. As will be seen in other embodiments, the bypass 130may be enlarged and may incorporate a fan upstream of the bypass toforce operating gas through the bypass. The bypass may allow for coolingof the nuclear fuel chamber 106 to avoid overheating of the nuclearpower generation apparatus 100. The bypass may be modified as needed toachieve this and other benefits or eliminated in certain configurationsto achieve other benefits.

As the operating gas exits the turbine assembly 618, the gas is releasedinto the containment vessel 102 for traveling along circulation path 110back to the inlet assembly 104. As shown in FIG. 1, downstream of theturbine assembly 618, the containment vessel 102 widens allowing for areduction in pressure and temperature in the operating gas. That is, thecirculation path 110 defined by the containment vessel 102 has a firstdiameter and a second diameter, the second diameter being larger thanthe first diameter and disposed downstream of the first diameter. Suchis the case with each of the embodiments shown in FIGS. 1-5 and 16. Inparticular, the significant expansion and reduction in pressure of theoperating gas after it passes the turbine assembly 618 and is dispersedinto the significantly greater volume of the containment vessel 102 mayassist in cooling of the operating gas. Further, the blades of theturbine assembly 618 included in the apparatus may be configured in away to aid the dispersion of the operating gas, including into theexpanded area of the circulation path. The containment vessel 102 mayinclude other components to cool the gas, such as the inner wall 128being cooled externally, cooling pipes located in the interior of thecontainment vessel 102, or a combination thereof as well as othercooling mechanisms.

Details of the inlet assembly 104, nuclear fuel chamber 106, and exhaustassembly 108 are provided in FIGS. 7, 10A, and 6, respectively. Forinstance, FIG. 7 illustrates a detail view of an axial compressor inletassembly in accordance with some embodiments discussed herein. Inparticular, FIG. 7 illustrates a detail view of compressor 712. Thecompressor 712 is connected to the downstream components by a driveshaft (e.g., 120 in FIG. 1). FIG. 10A illustrates a detail view of anuclear fuel chamber in accordance with some embodiments discussedherein. In particular, FIG. 10A illustrates the nuclear fuel elements1014 with flowpath 1015 showing the flow of operating gas around andthrough the nuclear fuel elements 1014. FIG. 6 illustrates a detail viewof an exhaust assembly and turbine assembly in accordance with someembodiments discussed herein. In particular, FIG. 6 illustrates nozzle616 and turbine assembly 618 as well as the drive shaft (e.g., 120 inFIG. 1) connecting the upstream inlet assembly components to the turbineassembly 618.

In some embodiments, the inlet assembly 104, nuclear fuel chamber 106,and exhaust assembly 108 may include other components and/orconfigurations without deviating from the intent of the presentdisclosure. For instance, in some embodiments, a centrifugal compressor,such as the centrifugal compressor 812 shown in FIG. 8 may be usedinstead of the axial compressor 712 shown in FIG. 1 and FIG. 7. Inparticular, FIG. 8 illustrates a detail view of a centrifugal compressor812 inlet assembly in accordance with some embodiments discussed herein.The centrifugal compressor 812 is connected via drive shaft (e.g., 120in FIG. 1) to the downstream components. The centrifugal compressor 812is connected to the downstream components, such as turbine assembly 618via a drive shaft. A centrifugal compressor may provide for a largerintake area thereby improving efficiency. Such larger intake areabecomes particularly important in stationary systems (as compared, forexample, to the intake area of jet engines on a plane in a flight).

Unlike traditional jet engines, the present apparatus is generallystationary (though the apparatus and/or certain components may bemovable in certain embodiments). The emphasis in the present apparatusis on axial velocity rather than thrust. Thus, the present apparatus maynot need certain components traditionally found in jet engines, such asboth a high pressure compressor and a low pressure compressor. Further,the compressors may not need diffusers, as such may create drag on thegas flow in the apparatus. The apparatus may be a closed system or anopen system using ambient gas similar to jet engines.

As noted above, the embodiment illustrated in FIG. 1 shows a bypass 130.In some embodiments, a fan, such as fan 932 shown in FIG. 9, may beadded upstream of the compressor to further direct the operating gasinto the gas propellant chamber 126 and/or the bypass 130. As notedabove, the bypass 130 may allow for cooling and thus regulation of thenuclear fuel chamber. In such embodiments, the assembly shown in FIG. 9may be incorporated into the nuclear power generation apparatus 100instead of the inlet assembly 104 shown in FIG. 1. In particular, FIG. 9illustrates a detail view of a fan 932 and compressor 912 connected tothe downstream components by a drive shaft (e.g., 120 in FIG. 1) inaccordance with some embodiments discussed herein.

In the embodiment illustrated in FIG. 1, the operating gas flows aroundand in between nuclear fuel elements. Such configuration is furtherillustrated in FIG. 10A. In some embodiments, the nuclear fuel elementsmay be configured such that the operating gas flows around the elements,instead of between elements. For instance, in some embodiments, thenuclear fuel elements 1114 of FIG. 10B may be used instead of theconfiguration shown in FIG. 1 allowing the operating gas to flow aroundthe nuclear fuel elements 1114 in flowpath 1115. In particular, FIG. 10Billustrates a detail view of a fuel core in accordance with someembodiments discussed herein. Further, in some embodiments, the nuclearfuel elements may be arranged in a fuel element lattice (i.e., fuelelements arrayed in a geometric matrix) designed to optimize theoperating parameters desired for the present apparatus. Flow channelsfor the operating gas may extend through the lattice. Variations on theconfiguration of the nuclear fuel elements and nuclear fuel chamber maybe available without deviating from the intent of the presentdisclosure.

In the embodiment illustrated in FIG. 1, the exhaust assembly 108includes a nozzle 616. In some embodiments, the exhaust assembly 108 maybe modified to resemble the detail image shown in FIG. 12 where aturbine assembly 1218 is in line with the exit of the nozzle 1216. FIG.12 illustrates a detail view of an exhaust assembly and turbine assemblyin accordance with some embodiments discussed herein. The turbineassembly 1218 is connected to a drive shaft (e.g., 120 in FIG. 1) whichis connected upstream to the inlet assembly components. Such positioningof the turbine assembly 1218 in line with the nozzle 1216 may decreasethe size of the apparatus allowing for a more compact design and mayimprove the efficiency of the apparatus in some embodiments.

Further, in some embodiments, the exhaust assembly 108 may be modifiedto resemble the detail image shown in FIG. 13 where the turbine assembly1318 includes a first turbine 1319 in line with the exit of the nozzle1316 and connected to a drive shaft (e.g., 120 in FIG. 1) which isconnected upstream to the inlet assembly components. The turbineassembly 1318 includes a second turbine 1323 in communication with astator belt 1321 and connected to the shaft 1320 to convert kineticenergy to rotational energy and then to electricity through therotor/stator combination. Such configuration may reduce the size of thedesign by including the generator in the apparatus and may improve theefficiency of the apparatus in some embodiments. The dotted lines shownin FIG. 13 indicate that an additional generator and/or flywheel may beincluded in some embodiments.

FIG. 2 illustrates a partial section view of a nuclear power generationapparatus in accordance with some embodiments discussed herein. Inparticular, FIG. 2 illustrates a nuclear power generation apparatus 200comprising a containment vessel 202 housing a gas propellant chamber 226which includes an inlet assembly 204, nuclear fuel chamber 206, andexhaust assembly 208. The containment vessel 202 also defines acirculation path 210 for the operating gas to circulate in the closedsystem. As shown in FIG. 2, in this embodiment, the inlet assembly 204includes a compressor 712, such as an axial compressor as illustrated inFIG. 2, disposed in the inlet port or first end of the annular body ofthe gas propellant chamber 226. In the embodiment illustrated in FIG. 2,the inlet port of the annular body of the gas propellant chamber 226 hasa cross section that decreases along the length of the inlet port wherethe compressor 712 is disposed. Such restriction in the cross sectionmay help to compress the operating gas to be directed to the nuclearfuel chamber. The nuclear fuel chamber 206 includes nuclear fuelelements 1014, and the exhaust assembly 208 includes a nozzle 1216 and aturbine assembly 1218. The nozzle 1216 forms the exhaust port or thesecond end of the annular body of the gas propellant chamber 226. Thecompressor 712 is connected to the turbine assembly 1218 by a shaft 220.The turbine assembly 1218 is also connected to a generator 222, shownschematically, and a flywheel 224.

In the embodiment illustrated in FIG. 2, the containment vessel 202includes cooling pipes 232 disposed along the circulation path 210 forcooling the operating gas prior to re-entry into the inlet assembly 204.FIG. 2 illustrates one configuration of the cooling pipes 232, however,various configurations are available without deviating from the intentof the present disclosure. For instance, one or more cooling pipes 232may be disposed in smaller sections or multiple sections along the flowpath to improve the cooling and gas transportation of the operating gasthrough the apparatus.

As noted in the description of FIG. 1 and shown in FIG. 2, thecompressor 712, turbine assembly 1218, generator 222, and flywheel 224rotate along the same axis. However, in other embodiments, one or moreof the components may rotate along a different axis. For instance, insome embodiments, it may be desired to have the flywheel 224 rotatealong an axis different than that of the compressor 712 and turbineassembly 1218.

Also as noted with respect to FIG. 1, in the embodiment illustrated inFIG. 2, a by-pass is disposed between the gas propellant chamber 226 andthe inner wall 228 of the containment vessel. As will be seen in otherembodiments, the bypass 230 may be enlarged and may incorporate a fanupstream of the bypass to force operating gas through the bypass, suchas the fan 932 shown in FIG. 9. The bypass may allow for cooling of thenuclear fuel chamber 206 to avoid overheating of the nuclear powergeneration apparatus 200. The bypass may be modified as needed toachieve this and other benefits or eliminated in certain configurationsto achieve other benefits.

Details of the inlet assembly 204, nuclear fuel chamber 206, and exhaustassembly 208 are provided in FIGS. 7, 10A, and 12, respectively.However, the components in the inlet assembly 204, nuclear fuel chamber206, and exhaust assembly 208 may be modified to resemble the componentsshown in the detail views of FIGS. 8-9, 10B, and 13 in variouscombinations. For instance, an axial compressor or a centrifugalcompressor, with or without a fan, may be used in the embodimentillustrated in FIG. 2 as shown in FIGS. 7-9. In addition, nuclear fuelelements shown in FIGS. 10A and 10B may alternatively be used in thenuclear fuel chamber 206. Further, the exhaust assembly may includenozzles, turbines, and/or rotor/stator combinations as shown in FIGS. 6and 13.

FIG. 3 illustrates a section view of a nuclear power generationapparatus in accordance with some embodiments discussed herein. Inparticular, FIG. 3 illustrates a nuclear power generation apparatus 300comprising a containment vessel 302 housing a gas propellant chamber 326which includes an inlet assembly 304, nuclear fuel chamber 306, andexhaust assembly 308. The containment vessel 302 also defines acirculation path 310 for the operating gas to flow in the closed system.As shown in FIG. 3, in this embodiment, the inlet assembly 304 includesa compressor 712, such as an axial compressor as illustrated in FIG. 3,disposed in the inlet port or first end of the annular body of the gaspropellant chamber 326. In the embodiment illustrated in FIG. 3, theinlet port of the annular body of the gas propellant chamber 326 has across section that decreases along the length of the inlet port wherethe compressor 712 is disposed. Such restriction in the cross sectionmay help to compress the operating gas to be directed to the nuclearfuel chamber. The exhaust assembly 308 includes a nozzle 1216 and aturbine assembly 1218. The nozzle 1216 forms the exhaust port or thesecond end of the annular body of the gas propellant chamber 326. Thecompressor 712 is connected to the turbine assembly 1218 by a shaft 320.The turbine assembly 1218 is also connected to a generator 322, shownschematically, and a flywheel 324.

In the embodiment illustrated in FIG. 3, the containment vessel 302 isof a double-wall construction with a first surface 302 a and a secondsurface 302 b, the first surface being disposed between the secondsurface 302 b and the circulation path 310. In some embodiments, acooling mechanism, such as a heat exchanger or coolant may be presentbetween the first surface 302 a and the second surface 302 b. In someembodiments, the pressure of the area between the first surface 302 aand the second surface 302 b may be different than the pressure of thecirculation path 310. For instance, the first surface 302 a may bedefined by an inner containment vessel layer and the second surface 302b may be defined by an outer containment vessel layer. A coolingmechanism may be disposed between the two vessel layers. A vacuum may beestablished between the two vessel layers. Various modifications can bemade without deviating from the intent of the present disclosure.

In the embodiment illustrated in FIG. 3, the nuclear fuel chamber 306includes interior flow paths 315 disposed in a spiral or helicalconfiguration such that the operating gas continues traveling in aspiral path after exiting the compressor. In particular, the nuclearfuel chamber 306 includes interior flow paths 315 adjacent to nuclearfuel elements 314 such that the operating gas continues traveling on thespiral or helical path initiated by the compressor. Accordingly, anyloss in rotational momentum due to the operating gas changing to astraight path may be mitigated. The helical flow paths may minimize dragat the nuclear fuel chamber inlet and outlet while also maintaining aspiral flow to optimize the speed and angle of impact of the operatinggas when striking the turbine blades. FIG. 3 illustrates a section viewto show the inside of the fuel-core chamber. While the nuclear fuelchamber 306 is stationary in FIG. 3, in some embodiments, the nuclearfuel chamber 306 may rotate along the shaft 320 along with thecompressor 712 and turbine assembly 1218.

The spiral configuration of the interior flow paths 315 allows the gasto spiral through the nuclear fuel chamber 306 to keep the gas movingthrough the apparatus. Such configuration may allow the interior flowpaths 315 to more evenly distribute heat to gas. The spiralconfiguration may also allow for a reduced size of the nuclear fuelchamber while maintaining a long contact path between the operating gasand the fuel core.

As shown in FIG. 3, the nuclear fuel chamber 306 includes interior flowpaths 315 disposed in a spiral or helical configuration. To form thespiral or helical flow path, the nuclear fuel chamber 306 may includefuel elements with helical groves, helically shaped elements with gaspassages, graphite or metal blocks with helical passages, or imbeddedfuel as well as a liquid fuel tank with helical pipes following theneeded flow shape. Various methods of forming the spiral or helical flowpath can be implemented taking advantage of all reactor core designs anddeveloping new reactor core designs—e.g., molten salt cores and solidcores.

As noted in the description of FIG. 1 and shown in FIG. 3, thecompressor 712, turbine assembly 1218, generator 322, and flywheel 324rotate along the same axis. However, in other embodiments, one or moreof the components may rotated along a different axis. For instance, insome embodiments, it may be desired to have the flywheel 324 rotatealong an axis different than that of the compressor 712 and turbineassembly 1218.

Also as noted with respect to FIG. 1 and shown in the embodimentillustrated in FIG. 3, a bypass is disposed between the gas propellantchamber 326 and the inner wall 328 of the containment vessel. In someembodiments, the bypass 330 may be enlarged and may incorporate a fanupstream of the bypass to force operating gas through the bypass, suchas the fan 932 shown in FIG. 9. The bypass may allow for cooling of thenuclear fuel chamber 306 to avoid overheating of the nuclear powergeneration apparatus 300. The bypass may be modified as needed toachieve this and other benefits or eliminated in certain configurationsto achieve other benefits.

Details of the inlet assembly 304 and exhaust assembly 308 are providedin FIGS. 7 and 12, respectively. However, the components in the inletassembly 304 and exhaust assembly 308 may be modified to resemble thecomponents shown in the detail views of FIGS. 6, 8-9, and 13. Forinstance, an axial compressor or a centrifugal compressor, each with orwithout a fan, may be used in the embodiment illustrated in FIG. 3. Whena centrifugal compressor is used, no diffuser may be needed. Further,the exhaust assembly may include nozzles, turbines, and/or rotor/statorcombinations as shown in FIGS. 6 and 13.

FIG. 11 illustrates a cross-section of the nuclear fuel chamber 306along line 11-11 shown in FIG. 3 in accordance with some embodimentsdiscussed herein. In particular, FIG. 11 illustrates the entrance to thenuclear fuel chamber 306 showing the interior flow paths 315 throughwhich the operating gas enters the nuclear fuel chamber 306. Not shownfrom this view are the nuclear fuel elements 314 which are enclosed inthe nuclear fuel chamber 306. The shaft 320 runs through the center ofthe nuclear fuel chamber 306. FIG. 11 also illustrates a cross sectionof the gas propellant chamber 332, bypass 330, interior wall of thecontainment vessel 328, cross section of the containment vessel 334, andcontainment vessel 302 along line 11-11. As shown in FIG. 11, thenuclear fuel chamber 306 includes multiple interior paths 315 for theoperating gas to enter the nuclear fuel chamber 306, to travel throughthe nuclear fuel chamber 306, and to be heated by the nuclear fuelelements housed in the nuclear fuel chamber 306.

FIG. 4 illustrates a partial section view of a nuclear power generationapparatus in accordance with some embodiments discussed herein. Inparticular, FIG. 4 illustrates a nuclear power generation apparatus 400comprising a containment vessel 402 housing a gas propellant chamber 426which includes an inlet assembly 404, fuel-core chamber 406, and exhaustassembly 408. The containment vessel 402 also defines a circulation path410 for the operating gas to flow in the closed system. As shown in FIG.4, in this embodiment, the inlet assembly 404 includes a compressor 912,such as an axial compressor as illustrated in FIG. 4, disposed in theinlet port or first end of the annular body of the gas propellantchamber 426. In the embodiment illustrated in FIG. 4, the inlet port ofthe annular body of the gas propellant chamber 426 has a cross sectionthat decreases along the length of the inlet port where the compressor912 is disposed. Such restriction in the cross section may help tocompress the operating gas to be directed to the nuclear fuel chamber.The nuclear fuel chamber 406 includes nuclear fuel elements 1014, andthe exhaust assembly 408 includes a nozzle 1316 and a turbine assembly1318. The nozzle 1316 forms the exhaust port or the second end of theannular body of the gas propellant chamber 426. The compressor 912 isconnected to the turbine assembly 1318 by a shaft 420.

In the embodiment illustrated in FIG. 4, the exhaust assembly 408includes a turbine assembly 1318 which includes a first turbine 1319 inline with the exit of the nozzle 1316 and connected to the shaft 420which is connected upstream to the inlet assembly components. Also inthe embodiment illustrated in FIG. 4, a second turbine 1323 is incommunication with a stator belt 1321 and is connected to the shaft 420to convert kinetic energy to rotational energy and then to electricitythrough the rotor/stator combination. Also in the embodiment illustratedin FIG. 4, a circulation fan 932 is connected to the shaft 420 in theinlet assembly downstream of the compressor 912 to assist in drawing theoperating gas into the inlet assembly and to accelerate and direct theoperating gas entering the inlet assembly. Such positioning of theturbine assembly 1318 in line with the nozzle 1316, with an additionalset of turbine blades 1323, as well as incorporating the generatorinside the containment vessel 402, may decrease the size of theapparatus allowing for a more compact design and may improve theefficiency of the apparatus in some embodiments. The integration of theheat source with the conversion assembly provides reduced overall systemdimensions. The nuclear fuel chamber can be designed so that thepressure and temperature at the outlet of the nuclear fuel chambersatisfy the velocity required at the inlet of the conversion assemblyfor the configuration. This is the advantage of using a nuclear reactor(potential for very high power density) and integrating the components.

As shown in FIG. 4 by the dotted lines, the turbine assembly 1318 in theembodiment illustrated in FIG. 4 may also be connected to a generatorand a flywheel.

As noted in the description of FIG. 1, the compressor 912 and turbines1319, 1323 rotate along a single axis. However, in other embodiments,the one or more of the components may rotated along a different axis.

In the embodiment illustrated in FIG. 4, a bypass is disposed betweenthe gas propellant chamber 426 and the inner wall 428 of the containmentvessel. A circulation fan 932 is disposed upstream of the bypass toforce operating gas through the bypass. The bypass may allow for coolingof the nuclear fuel chamber 406 to avoid overheating of the nuclearpower generation apparatus 400. The gas flowing through the bypass inthis configuration, after it has been accelerated by the circulation fanin the inlet assembly, may augment the kinetic energy to be converted torotational energy. The bypass may be modified as needed to achieve thisand other benefits.

Details of the inlet assembly 404, nuclear fuel chamber 406, and exhaustassembly 408 are provided in FIGS. 9, 10A, and 13, respectively.However, the components in the inlet assembly 404, nuclear fuel chamber406, and exhaust assembly 408 may be modified to resemble the componentsshown in the detail views of FIGS. 6-8, and 10B. For instance, an axialcompressor or a centrifugal compressor may be used in the embodimentillustrated in FIG. 4. In addition, nuclear fuel elements shown in FIGS.10A and 10B may alternatively be used in the nuclear fuel chamber 406.

In some embodiments, a rotor/stator combination may be incorporated intothe nozzle. FIG. 5 illustrates a partial section view of a nuclear powergeneration apparatus in accordance with some embodiments discussedherein. In particular, FIG. 5 illustrates a nuclear power generationapparatus 500 comprising a containment vessel 502 housing a gaspropellant chamber 526 which includes an inlet assembly 504, nuclearfuel chamber 506, and exhaust assembly 508. The containment vessel 502also defines a circulation path 510 for the operating gas to flow in theclosed system. As shown in FIG. 5, in this embodiment, the inletassembly 504 includes a compressor 712, such as an axial compressor asillustrated in FIG. 5, disposed in the inlet port or first end of theannular body of the gas propellant chamber 526. In the embodimentillustrated in FIG. 5, the inlet port of the annular body of the gaspropellant chamber 526 has a cross section that decreases along thelength of the inlet port where the compressor 712 is disposed. Suchrestriction in the cross section may help to compress the operating gasto be directed to the nuclear fuel chamber. The nuclear fuel chamber 506includes nuclear fuel elements 1014.

In the embodiment illustrated in FIG. 5, the exhaust assembly 508includes a nozzle 516 that includes angled blades 540 disposed withinthe nozzle to allow for the nozzle 516 to rotate as the operating gasenters and exits the nozzle 516. The nozzle 516 forms the exhaust portor the second end of the annular body of the gas propellant chamber 526.The nozzle 516 is coupled to a rotor 536 that rotates with the nozzle516. The rotor 536 is in communication with a stator 538 by way of ahigh performance bearing such as a magnetic bearing. The stator 538 isconnected to the nuclear fuel chamber 506 and is stationary as the rotor536 rotates with the nozzle 516. The embodiment illustrated in FIG. 5allows for further integration of the components in the apparatus byincorporating the electricity generator in the exhaust assembly andrelies on a high gas velocity to rotate the nozzle 516.

In some embodiments, a flywheel 524 may be incorporated in theapparatus. As illustrated in FIG. 5, the compressor 712 is rotationallyconnected to a flywheel 524 by a shaft 520 running through the nuclearpower generation apparatus 500. The compressor 712 and flywheel 524rotate along the same axis. However, in other embodiments, thecomponents may rotate along different axes. In the embodimentillustrated in FIG. 5, the flywheel 524 is positioned outside of thecontainment vessel. In other embodiments, an external flywheel may notbe used. As noted previously, a flywheel may be added to any of theembodiments disclosed here. The flywheel may be internal or external tothe containment vessel. In some embodiments, the nuclear fuel chamber506 may rotate with the nozzle 516 and rotor 516, especially for spaceapplications since the gravitational forces may be minimal. Forinstance, the nuclear fuel chamber 506 may be connected to the nozzle516 and rotor 536 so that the nuclear fuel chamber 506 is rotationallycoupled to the nozzle 516 and rotor 536. Any of the embodimentsdisclosed herein may include a rotating nuclear fuel chamber.

FIG. 15 illustrates a cross-section of the exhaust assembly nozzle alongline 15-15 shown in FIG. 5 in accordance with some embodiments discussedherein. In particular, FIG. 15 illustrates the nozzle blades 540 asoperating gas would exit the nuclear fuel chamber 506 and enter theexhaust assembly 508 including the nozzle 516. The shaft 520 is shown inthe center running through the gas propellant chamber 526. FIG. 15illustrates the cross section of the nozzle 516, cross section of thecontainment vessel 534, and the containment vessel 502 along line 15-15.

Details of the inlet assembly 504 and nuclear fuel chamber 506 areprovided in FIGS. 7 and 10A, respectively. However, the components inthe inlet assembly 504 and nuclear fuel chamber 506 may be modified toresemble the components shown in the detail views of FIGS. 8-9 and 10B.For instance, an axial compressor or a centrifugal compressor may beused in the embodiment illustrated in FIG. 5. In addition, nuclear fuelelements shown in FIGS. 10A and 10B may alternatively be used in thenuclear fuel chamber 506.

FIG. 16 illustrates a partial section view of a nuclear power generationapparatus in accordance with some embodiments discussed herein. Inparticular, FIG. 16 illustrates a nuclear power generation apparatus1600 comprising a containment vessel 1602 housing a gas propellantchamber 1626 which includes an inlet assembly 1604, nuclear fuel chamber1606, and exhaust assembly 1608. The containment vessel 1602 alsodefines a circulation path 1610 for the operating gas to flow in theclosed system. As shown in FIG. 16, in this embodiment, the inletassembly 1604 includes a compressor 712, such as an axial compressor asillustrated in FIG. 16, disposed in the inlet port or first end of theannular body of the gas propellant chamber 1626. In the embodimentillustrated in FIG. 16, the inlet port of the annular body of the gaspropellant chamber 1626 has a cross section that decreases along thelength of the inlet port where the compressor 712 is disposed. Suchrestriction in the cross section may help to compress the operating gasto be directed to the nuclear fuel chamber. The nuclear fuel chamber1606 includes nuclear fuel elements 1014, and the exhaust assembly 1608includes a nozzle 616 and turbine assembly 618. The nozzle 616 forms theexhaust port or the second end of the annular body of the gas propellantchamber 1626. The compressor 712 is connected to a turbine assembly 618,a generator 1622, and a propeller 1624 by a shaft 1620 running throughthe nuclear power generation apparatus 1600. The compressor 712, turbineassembly 618, and propeller 1624 rotates along the same axis. However,in other embodiments, the components may rotate along different axes.The embodiment illustrated in FIG. 16 also includes bypasses 1630 alonginner wall 1628 of containment vessel 1602 to allow for cooling of thenuclear fuel chamber 1606 and improve the efficiency of the system.

In the embodiment illustrated in FIG. 16, the exhaust assembly 1608includes a nozzle 616. In the embodiment illustrated in FIG. 16, thepropeller 1624 is positioned outside of the containment vessel and maybe used for propulsion, while the apparatus also generates electricityand district heating, for example for use on board a submarine. In otherembodiments, an external propeller may not be used. In the embodimentillustrated in FIG. 16, heat exchangers 1640 are also included forprocess heat and to efficiently cool the operating gas prior to re-entryinto the inlet assembly 1604.

The present apparatus provides the superior qualities of nuclear fuel(its remarkable energy per mass and its long-life) in a gas-propellantsystem to create an electricity generating system taking betteradvantage of the nuclear fuel qualities and providing a simpler,integrated design that eliminates some of the complex thermal conversionmachinery and related significant energy losses from current nuclearreactor designs, as well as the risks and maintenance associated withsuch machinery. This apparatus also provides for the generation ofmechanical and/or thermal energy in addition to electricity. Thesimpler, integrated design also allow for substantially greater designflexibility as well as the capability to optimize the expectedelectricity and other energy production through the adjustment ofvarious design features, such as the type and configurations of thecomponents in the apparatus (e.g., the compressor, turbine, nozzles,rotor/stator belts, etc.), the arrangement of nuclear fuel elementlattice and other components in the fuel core, the type of the operatinggas, and the configuration of the containment vessel. By applyingcurrent technologies and methodologies through computer modeling andother analyses, substantially enhanced design specifications can beachieved in a cost-effective manner and these processes can be easilyadapted to provide alternative designs for different, specificoperational uses intended for the present apparatus.

The present apparatus is also an inherently safer design than that ofmany current nuclear reactors because it may have a lower nuclear corepower density, could use an inert gas as the coolant, and eliminates allor most of the thermal conversion machinery. The apparatus is capable ofbeing factory manufactured, which would result in lower and morepredictable capital costs. The apparatus could be fueled in the factoryunder controlled circumstances, and then safely transported to itsonsite production location, making it more proliferation resistant.Additionally, the more efficient and simpler design of the invention mayresult in the use of a smaller quantity of nuclear fuel, and for alonger period of time, thus enhancing its safety features and providingadvantages over other nuclear reactor designs as far as nuclear wastedisposal and being proliferation resistant. The safety and simpleroperations of the apparatus allows it to be sited at desalinationplants, as well as adjacent to industrial and other facilities toprovide such facilities process heat in addition to electrical power.These same qualities would also allow for broad deployment for themechanical energy generated by the apparatus to be used in variousapplications. Further, the smaller, more compact design would reduce thedifficult siting or location issues currently considered for nuclearreactors.

The present apparatus may utilize, with adaptions understood by thosepersons skilled in the art, current state-of-the-art materials anddesigns for jet engines and thermal nuclear propulsion. The presentapparatus also generally permits advances made in jet engine designs andthermal nuclear propulsion to be incorporated either through the designsof future systems or by minor retrofitting of then existing reactorsthat use the apparatus.

Many modifications and other embodiments of the inventions set forthherein will come to mind to one skilled in the art to which theseembodiments of the invention pertain having the benefit of the teachingspresented in the foregoing descriptions and the associated drawings.Therefore, it is to be understood that the embodiments of the inventionare not to be limited to the specific embodiments disclosed and thatmodifications and other embodiments are intended to be included withinthe scope of the appended claims. Although specific terms are employedherein, they are used in a generic and descriptive sense only and notfor purposes of limitation.

1.-20. (canceled)
 21. An apparatus for generating electricity comprising: a gas propellant chamber comprised of an annular body defining first and second ends, the first end of the annular body defining an inlet assembly that is configured to draw operating gas into the gas propellant chamber and the second end defining an exhaust assembly that is configured to expel operating gas from the gas propellant chamber, the second end of the annular body forming a nozzle having a progressively decreasing circumference along a direction of the operating gas entering and exiting the gas propellant chamber; a nuclear fuel chamber positioned within the annular body of the gas propellant chamber between the first and second ends, the nuclear fuel chamber housing a nuclear fuel core comprising fissile material; a compressor positioned proximate the first end of the gas propellant chamber, the compressor configured to compress the operating gas prior to entry into the nuclear fuel chamber; a conversion assembly positioned proximate the second end of the gas propellant chamber, the conversion assembly configured to convert kinetic energy of the operating gas exiting the nuclear fuel chamber into rotational energy; a drive shaft extending axially through the gas propellant chamber between the first and second ends, the drive shaft coupling the compressor to the conversion assembly; and one or more generators, the one or more generators configured to convert the rotational energy of the conversion assembly into electricity.
 22. The apparatus of claim 21, wherein a first generator of the one or more generators is integrated into the conversion assembly.
 23. The apparatus according to claim 22, wherein the conversion assembly comprises a turbine assembly, the turbine assembly comprising one or more turbines connected to the drive shaft, at least one of the one or more turbines is in communication with a stator belt.
 24. The apparatus according to claim 23, wherein a first turbine is in line with an exit of the nozzle and a second turbine is positioned downstream of the nozzle.
 25. The apparatus according to claim 24, wherein the first turbine is in communication with the stator belt.
 26. The apparatus according to claim 24, wherein the second turbine is in communication with the stator belt.
 27. The apparatus according to claim 22, wherein the gas propellant chamber is disposed in a sealed containment vessel and a second generator is positioned external to the sealed containment vessel.
 28. The apparatus according to claim 22, wherein the conversion assembly comprises a turbine assembly, the turbine assembly comprising a turbine connected to the drive shaft, the turbine comprising a rotor, wherein the turbine and rotor are disposed in communicative proximity of a stator.
 29. The apparatus according to claim 21, wherein the nozzle is configured to rotate as the operating gas enters and exits the nozzle.
 30. The apparatus according to claim 29, wherein angled blades are disposed within an internal circumference of the nozzle.
 31. The apparatus according to claim 29, wherein the nozzle is connected to a rotor such that the rotor is configured to rotate with the nozzle.
 32. The apparatus according to claim 31, wherein the rotor is in communication with a stator.
 33. The apparatus according to claim 32, wherein the rotor and the stator comprise high performance bearings.
 34. The apparatus according to claim 33, wherein the high performance bearings are magnetic bearings.
 35. The apparatus according to claim 33, wherein the high performance bearings are oil bearings with gas seals.
 36. The apparatus according to claim 32, wherein the stator is coupled to the nuclear fuel chamber.
 37. The apparatus according to claim 32, wherein the conversion assembly comprises a turbine assembly, the turbine assembly comprising one or more turbines connected to the drive shaft, at least one of the one or more turbines positioned downstream of the nozzle.
 38. The apparatus according to claim 21, wherein at least one of the one or more generators is an electrostatic generator.
 39. The apparatus according to claim 21, wherein the gas propellant chamber is disposed in a sealed containment vessel and the one or more generators are positioned external to the sealed containment vessel.
 40. The apparatus according to claim 21, wherein at least one of the one or more generators is in communication with the conversion assembly and configured to initiate rotation of the operating gas in the apparatus. 